Girls in psychiatric care initiate sexual activity at an early age and engage in high rates of sexual risk-taking thereby increasing their exposure to HIV/AIDS. Family and partner processes influence girls' sexual socialization and sexual behavior, yet little is known about the role these factors play in predicting sexual debut and risky sexual behavior in troubled girls. The current project tests a model of HIV-risk that emphasizes the interplay of family and partner mechanisms and proposes that family processes increase troubled girls' HIV-risk directly and indirectly through girls' partner relationships. Study aims are to identify mother-daughter relationship factors, mother-daughter communication patterns (general and risk-specific), maternal attitudes and behavior, and girls' partner relationship characteristics that predict: (a) troubled girls' sexual debut, (b) risky sexual behavior among girls in psychiatric care, and (3) sexual risk-taking in theoretically important subgroups of troubled girls, i.e., internalizing, externalizing, and substance using. We will recruit 280 13-15 year-old girls and their mothers seeking outpatient mental health services at inner-city clinics in Chicago, and we will follow them for 2 years. Girls and their mothers will complete questionnaires, participate in interviews, and engage in three structured videotaped interaction tasks to assess the key constructs in the model. Thus, we will use multiple methods to predict sexual debut and risky sexual behavior in girls seeking mental health services. We will use structural equation modeling to test the associations specified in the model and to identify causal factors associated with troubled girls at highest HIV-risk, and we will use classification tree analysis via Optimal Data Analysis to investigate the predictive power of these psychosocial variables. The long-term significance of this research is to guide the development of family- based gender sensitive prevention programs for mothers and daughters receiving psychiatric care. Mother-daughter dyads are especially well-suited to HIV prevention efforts, because mothers play a central role in girls' sexual socialization, girls rely on mothers more than fathers for advice, support, and information about sex-related topics, the mother-daughter relationship is a key predictor of adolescent girls' sexual experience, and a sizable number of urban households are led by single mothers. Interventions that are effective in a clinical setting may then be adapted for girls with mental health problems in school-based settings. This study is part of an overall program of research designed to develop effective HIV prevention programs for troubled teens and their families.